The objective of this proposal is to obtain a state-of-the-art fluorescence activated cell sorter (FACS) and establish a FACS facility at the University of Pennsylvania School of Dental Medicine. The facility would serve as a resource to all investigators at the School of Dental Medicine and would be used to support several research projects currently funded by the NIH. These projects range from basic research into structure and biochemistry of oral tissues to molecular mechanisms involved in the pathogenesis of oral infections to clinical studies aimed at determining pathogenetic events in oral disease. Applications of the FACS will be varied and include: multicolor (up to 4) and multiparameter (up to 6) cell analysis and sorting, separation and isolation of human chromosomes, selection and cloning of hybridomas and transfected cells and analysis of several cellular processes (i.e., cell cycle, intracellular calcium levels, membrane permeability/potential). The FACS would not only support and facilitate current research projects, but also enhance our capability to extend these investigations in new directions.